Steemit has launched its promote option in the start of 2017 for the users of steemit it. And this promote option is helping lots of steemit users to promote Thier posts and reach to more audience and viewers.
You can promote your blogs just in 3 steps
Step 1] choose one of your blog which is good
Step 2 ] select or click on promote option. You can find promote option in the end of your blog on right side (see the picture
STEP 3] you can promote your blog for minimum 1 and click on promote 
WHAT BENIFITS HAS PROMOTING YOUR BLOG ?
1. If your blog have valuable information it will help lots of readers to gain knowledge
2. If the readers find your blog valuable they will upvote your blogs
3. Lots of user will follow you
4. You will gain more reputation point
5. Consistently promoting your blogs will helps you to become famous and familiar to lots of steemit users